Kaine made the announcement through a video posted on his Facebook page.
In the video, Kaine never mentions his time at the partisan DNC, but instead recounts his time as governor of Virginia, and promises to work across party lines.
"While we still have an awful lot of work to do to help Virginians who are struggling in a tough time, I know that Washington can learn a few things from Virginia," he says in the video.
Kaine's announcement comes after Sen. Jim Webb announced he'll be retiring from office after just one term.
On the Republican side, Tea Party activist Jamie Radtke is facing off against George Allen for the nomination.
Allen, served as governor from 1994 to 1998, and was elected to the Senate in 2000. He lost his seat to Webb in 2006.